


Finn: The Sequel

by wheel_pen



Series: Finn [9]
Category: Sherlock (TV)
Genre: Clones, Kid Fic, M/M
Language: English
Status: Completed
Published: 2015-10-03
Updated: 2015-10-10
Packaged: 2018-04-24 15:47:32
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 4,545
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/4925590
Author URL: https://archiveofourown.org/users/wheel_pen/pseuds/wheel_pen
Summary: <blockquote class="userstuff">
              <p>Finn remembers something very important from when he was in captivity, prompting John and Sherlock to add another new person to their family.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> The bad words are censored. That’s just how I do things.  
> This story has not been Britpicked. Please let me know if I get anything horribly wrong.  
> I hope you enjoy this AU. I own nothing and appreciate the chance to play in this universe.

Sherlock and Finn were being very well-behaved. John didn’t know how long this would last, but he was determined to celebrate the achievement later, because he was certain it was a record. They were all sitting on a hideous floral couch in his mother’s living room, with his mother showing Finn an album of old family photos. Sherlock was squeezed onto the far end, his arm around John’s shoulders, and, okay, he was playing with his phone with his other hand, but he had it on silent, and John gave his thigh a squeeze whenever he made a distracting noise in response to something he was reading. This kept him quiet and still, which was preferable to winging comments about John’s relatives—proclaiming Uncle Rob couldn’t possibly be Cousin Beatrix’s father because of his jumper pattern or something like that.

Finn had no such distraction from the onslaught of washed-out photos full of faces even John barely remembered. He had to sit next to his grandmother with the heavy album partially on his lap, and make intelligible noises as she pointed at people and told dull stories about them. He was doing very, very well and John was keeping a close eye on the time, ready to end it when he thought the limits of a six-year-old’s endurance had been reached. His mother _meant_ well, but she’d never been an especially empathetic person, and finding herself with a ready-made grandson and a slightly psychotic son-in-law had been a bit much for her. Hey, at least John didn’t have alcohol issues like Harry, right?

His mother turned to a fresh page and John decided Finn’s time was up. “Hey, Mum, how about we go out in the garden a bit, stretch our legs?” he suggested before she could speak.

“Oh, but I’ve just gotten to photos of you and your sister,” she protested regretfully.

“That’ll be a good place to start next time,” John persuaded, already sitting up. Simpler times, maybe happier to her, though John would disagree.

“Well, alright,” she acquiesced reluctantly, starting to close the album.

Finn put his hand in to stop her. “I’ve seen him before,” he said, pointing to a picture of a blond-haired young boy.

John narrowed his eyes at his son, sensing something was off about his body language and expression. The child was smart enough to make a run for it at the first opportunity, not drag things out. “Oh yes, that’s John,” his mother explained, happy to continue. “How clever you are to recognize him! The eyes never change, do they?”

“No, I’ve seen _him_ before,” Finn insisted, and John nudged Sherlock to pay attention. “This boy right here.”

“Where did you see him, Finn?” John asked, resting a hand on his back.

“At the place I was before,” Finn replied thoughtfully, and John felt Sherlock tense beside him. “It was a long time ago, when I was really little. He said his name was Tutu.”

John’s mother relaxed. “Oh, you’re telling a funny story,” she decided. “How charming.”

“Tutu?” John repeated in confusion to Sherlock. The answer hit them both at the same time.

“Twenty-Two!”

“I’ll call Mycroft,” Sherlock announced, leaping up from the couch.

“Gotta go, Mum, we’ll call you later,” John said, hurrying Finn up so he could get his coat and shoes. “Can I borrow this? Thanks.” He yanked the photo of himself from the album.

“But where are you…?” his mother asked, completely mystified.

John wanted to convince her not to worry, so he tried chuckling a little, but it burbled out as more of a nervous giggle, and he couldn’t quite conceal the sick feeling building in the pit of his stomach. “It’s fine, it’s all fine, really,” he claimed.

In the background he could hear Sherlock snapping into his phone, “ _Busy_? He’s _always_ busy! Put the g-----n call through anyway!” This apparently got him disconnected.

Finn tugged on John’s arm. “Have I done something wrong?” he asked with uncertainty.

“No, no, no, no, not at all,” John assured him, smoothing down his dark curls and kissing them. “We just have to go now. Do you have everything? Tell Granny good-bye.” He darted over to Sherlock.

“I’m texting him, private line,” he muttered in frustration. The message was short and sent another chill down John’s spine. _15 SH 22 JW_.

They waited tensely for a few seconds. There was probably something John could be doing that would expedite their exit, but he couldn’t think clearly, and to be honest he didn’t want to leave Sherlock or Finn, who now clung to his hand. The thought of another child being kept captive like Finn was, of someone targeting _him_ to make that child—he didn’t realize he was gripping Sherlock’s arm until the other man squeezed his own in turn and gave him a look of determination. They _would_ get to the bottom of this. He couldn’t ask for a better man to have on the job.

His phone buzzed and they both read the message. _Do you need a car?_ John almost sighed with relief—make that the _two_ best men.

“We’ll take a cab,” Sherlock decided. “Let’s go.”

“Bye, Mum, I’ll call you later,” John promised as they rushed out the door.

They put Finn between them in the back of the taxi and sent it racing to Mycroft’s office. “Tell that story again,” Sherlock ordered the boy, his gaze unwavering. “About this boy.” He held up the picture of John.

“It’s okay, you didn’t do anything wrong,” John assured the boy while Sherlock waited impatiently. “You did _very_ well with Granny and the pictures. But that’s a very important story, and we want to hear it again.”

“The whole thing,” Sherlock specified. “But don’t make anything up.”

“Just take your time,” John soothed.

“But start now,” Sherlock insisted.

“I was at the other place,” Finn repeated, “and the lights went out. Not like they did at bedtime, but very suddenly. And all the humming stopped. And then these red lights came on, and the door that never opens—opened.”

“Sudden power outage, emergency light,” John murmured over his head.

“Emergency exits,” Sherlock concurred.

“So I went through the door,” Finn went on at their nod, “into the hallway, which was all red, and I went down the hall and around the corner a bit. And then I saw this boy.” He tapped the photo. “I think he was littler than me. I said hello, and my name’s Finn—well, Fif,” he corrected, trying to be accurate. “And I asked his name and he said, Tutu. And we were going to look around more, but then I got very sleepy. And when I woke up I was back in my bed and the lights were on and that door wouldn’t open.”

“Knockout gas?” John proposed.

Sherlock agreed. “Why didn’t you say this before?” he asked Finn. John pinched his shoulder, trying to indicate he shouldn’t be so abrupt.

“I didn’t remember,” Finn told them. “I didn’t remember until I saw the picture. Is that bad?” He looked between the two of them nervously.

Naturally John was the first to comfort him. “No, it’s fine,” he assured him. “We just want to find that little boy. Like Uncle Mycroft found you. That was good, wasn’t it?” Finn nodded vigorously.

“We’ll find him,” Sherlock stated, with certainty.


	2. Chapter 2

Sherlock released Finn from the constriction of his coat (why did John insist he wear it? He was obviously warm enough) and sent him off to play at the park, sweeping the area for deviants (none found, alas) before settling down at one of the picnic tables.

“Hello, Sherlock. How are you today?”

Somehow, despite his keen powers of observation, he had failed to notice the blond woman on the other side of the table. She was stealthy like a ninja, he had often thought, and bore close watching.

“Hello.” He ignored the question, which John had explained was a (mere) social nicety, and not leave to recite a detailed report.

“Melanie,” she added randomly, and Sherlock blinked at her. “In case you forgot my name.”

To forget something one had to remember it at some point and Sherlock immediately swept it from his mind. This was ‘the mother of Finn’s annoying playmate’ and that was a far better identifier for Sherlock’s purposes than Melissa or Melody or whatever she’d said. “You have a second child,” he deduced. “From the wear pattern on your handbag I would say roughly four years old.”

“Yes, my son, Taran,” she agreed. “You’ve met him.”

Sherlock doubted that. Or at least, that was something else he’d deleted, though now it might have been relevant. “John and I have recently acquired a second child, a four-year-old male,” he announced, and the woman raised an eyebrow. “His name is Arthur.”

“Arthur Holmes?”

“No, Arthur Watson,” Sherlock corrected. “It seemed more egalitarian.” Not to mention, Arthur was the spitting image of John, and it just made more sense socially for them to share a name.

“Congratulations,” the woman said. She was able to converse while also keeping an eye on her offspring, which Sherlock found appropriately vigilant. “Where is he?”

“John’s bringing him,” Sherlock informed her. “He’s lacked socialization to this point and is rather shy. Also he doesn’t speak. Where’s yours?” If they were going to demand the whereabouts of four-year-olds.

“He’s at home with my husband,” she answered. “You’ve met him also.”

“Yes, I retained that memory to assist in future identification,” Sherlock assured her.

“Ah, a rare privilege.”

“Yes.” He was glad she understood that.

“Did you say he didn’t speak?” _Now_ she was just being dull, however.

“Yes,” Sherlock confirmed. “He makes sounds and seems to understand at an age-appropriate level, but as yet has not articulated any words.” He thought about what _he_ would want to know, when vetting Finn’s playmates (which he did not do, as John had swiftly assumed that duty). “Likely this is psychological trauma stemming from the poor conditions under which he was raised, which I expect is fully reversible.”

The woman frowned. “How was he raised?”

“That’s classified.” Mycroft was still sorting the whole thing out.

The woman took this well. “Lucky for him you and John came along,” she commented. “He’ll have a good home with you.”

“Yes.” That went without saying. Anything that was part of John was part of Sherlock, too. And Arthur was far preferable to other people who fit that description, like John’s tedious mother or his pointless sister. Who Sherlock had nonetheless (figuratively) embraced, given that John still claimed them.

A familiar cry caught his ear and, after sighting Finn playing happily on the merry-go-round, Sherlock swiftly left the table to relieve John of his caterwauling burden. “Sorry, he’s just—Maybe I shouldn’t—“

Sherlock flipped Arthur’s hood up and let him bury his face against the heavy black of Sherlock’s wool coat. John was more stressed by Arthur than he was by Finn, whether because Arthur seemed to cope less well with his isolation or just the general increase in duties, Sherlock wasn’t sure. However, Sherlock was now an experienced parent, and could easily assist.

“I’ll take him,” he stated. “We’ll go someplace quiet. But still nearby.” John was still looking distressed. “Try speaking to Martha, she’s very understanding today.”

“Yes, thank goodness,” John sighed, with a hint of sarcasm Sherlock didn’t get. He went to the picnic table and Sherlock carried Arthur off towards some less popular trees.

“You’d best attempt to calm down now,” Sherlock advised, wanting to give the boy a fair chance. “I’m not like John, I can stand here all day.” Actually he had some rather exciting fungus to get back to at home. But, it was _almost_ as interesting to observe how Arthur’s plastic little mind absorbed and adapted to his surroundings.

Gradually he reduced himself to snuffles and looked up. “Yes, we’re still at the park,” Sherlock confirmed. Arthur peeked at it over his shoulder and did not seem encouraged. “It can be rather ghastly,” Sherlock admitted. “So many people. Stupid people, I mean. Of course people in general don’t bother me.” Arthur blinked at him moistly. “The trick is,” Sherlock continued, “you learn to see what their weaknesses are, and then they don’t bother you so much. Shall we try an example?”

“Sherlock’s taken to him well,” Melanie noted.

“Yes, fortunately.” John and Sherlock had developed a cover story to avoid the weirder parts of the boys’ history, but he was never sure how well Sherlock stuck to it. “My ex—well, she wasn’t really—“

Melanie waved him off. “Sherlock already said it was classified.”

“Oh did he?” Melanie seemed darkly amused by this and John decided to leave it. “Yes, well… I was hoping we could set up something with Cimmy and Taran sometime, after Arthur’s gotten used to things, I mean.” He couldn’t help glancing back and now saw that Sherlock and Arthur were both facing the park, with Sherlock gesturing at people. “Lord, what is he teaching him?” John wondered.

Melanie patted his hand. “He’ll be good for all of you,” she predicted. “Balance Finn out, give him a playmate.”

“Oh, is that how it is for Cimmy and Taran?” John did not have good sibling relations to draw on for inspiration, and neither did Sherlock.

“Nah, right now they hate each other,” Melanie admitted easily. “But I think they’ll grow out of it.”

John hoped she was right, and that the same could be said for Finn and Arthur. They would, at the very least, be bonded by growing up in the crucible of the Holmes-Watson household. “Papa! Look, I found a worm!” Finn announced, bouncing over waving it aloft. “Can we take it home and dissect it?”

“Sure,” John agreed, pulling a plastic bag from his pocket. The childcare books were right, those _were_ handy to have around.

“Mummy, can I go to Finn’s house and dissect the worm, too?” Cimmy begged. “Please please please?”

“Well, go find your own worm first,” Melanie advised, and the two children went running off. “Let’s make it potluck at least.”

“BYOW,” John agreed with a chuckle. “Bring Your Own Worm.” Sherlock rejoined them, still clutching Arthur tightly. “We’re planning a worm dissection party,” John informed him. “That alright with you?”

Sherlock frowned. “I don’t think I have any spare worms,” he admitted. “I have some expendable caterpillars, however.”

“Sounds good to me,” John agreed. “What shall we do for party favors?”

“How many children are invited to this?” Sherlock wanted to know. “Perhaps Arthur and I could visit with Molly at the morgue instead—“

Melanie laughed, perhaps under the impression Sherlock was joking. Best keep it that way. “No, we need your ace dissecting skills,” John assured him. “It’s only Finn and Cimmy. Hey there, Arthur,” he added, seeing the boy peep out to survey the world. “Feeling better?” Melanie’s eyes pinged between them, noting the strong resemblance, but that was hardly unusual for father and son, right? “What have you and Daddy been talking about?”

“How to tell people’s secrets,” Sherlock responded forthrightly. “Vital observation and deduction skills don’t just develop spontaneously, John. They must be _honed_.”

“Well good.”

“For example, earlier I deduced that Margaret also has a four-year-old male child,” Sherlock pointed out proudly. “The wear pattern on her—“

“You’ve met him,” John interrupted, unimpressed. “And nothing you deduce about her counts until you get her name right. Twice in a row.” Sherlock looked rather put out by this, but John knew how to distract him. “Here’s the worm Finn found,” he said, passing the bag to him.

Indeed, Sherlock’s eyes lit up. “Ooh, _Eisenia veneta_ ,” he identified, holding it up to the light. “Average specimen, slightly distended saddle.”

Arthur watched the worm twitch and let out a squeal, and John took him in his arms, supposing that was predictable. “I think we’ve had our dose of the park today,” he decided, hefting the boy. “You’re coming over after a bit?” he checked with Melanie.

“BYOW,” she confirmed.

“Text when you leave the park,” he added to Sherlock. Then he gave him a kiss on the cheek, hoping that was at least as interesting as the worm.

“What? Oh, of course,” Sherlock claimed, and he actually put the worm down to stare after John as he left. John decided to count that as a victory.

**

The knock on the door set Finn to whooping. “It’s Uncle Greg, it’s Uncle Greg!” he shouted, bouncing around the living room.

“Do not call him that!” Sherlock ordered futilely. “He is neither my brother nor John’s, and therefore not your uncle.”

“It’s an honorific,” John told Sherlock as he headed for the door, because Sherlock clearly wasn’t going to answer it. “Could you put the tea on? Finn, indoor voice, please.” Sherlock huffed but did in fact get up and go to the kitchen, though who knew if tea would actually be produced.

John finally opened the door to see Greg standing there, and the man gave a big grin. “Hey there, John.”

“Greg, nice to see you, come in,” John encouraged, stepping aside.

Their visitor was immediately engulfed by Finn and Greg scooped him up. “How are you, little man?” he asked cheerfully.

“I’m alright,” Finn claimed, looking around eagerly. “Have you brought me a present?” he wanted to know. “I think you have.”

“Finn,” John warned, leaning back out of the kitchen. Sherlock had gotten distracted rearranging his chemicals on the upper shelves and needed prompting.

“You ought to have brought a present for Arthur as well,” Finn judged.

“Finnegan,” John repeated, more gravely. This time the boy looked chastened, knowing that if he got to ‘Finnegan Hamish Holmes’ a trip to his room by himself was the next stop, which was A Bit Not Good in John’s book.

“Well it just so happens I _did_ bring a present for both of you,” Greg promised, unoffended. He glanced around the floor. “Where _is_ the little fellow, anyway?”

“You’ve probably frightened him with all your shouting and stomping,” Sherlock predicted, going back to his chair. He couldn’t even figure out why John had insisted he go to the kitchen in the first place.

“I’m afraid Arthur will just have to get used to that,” John commented dryly, following him. He peered around the living room floor and finally spotted a small foot sticking out from under a tablecloth. “I think if you start playing, he’ll come out when he’s ready,” he suggested to Greg, settling down on the couch with a view of the open floor space.

Sherlock looked up from his tablet. “There was something about tea,” he remembered vaguely, as John rolled his eyes affectionately. “Oh, was _I_ supposed to put it on?”

“You can fetch it,” John delegated, pleased that he had at least made an attempt.

“What did you bring, what did you bring?” Finn asked eagerly, as Greg got down on the floor with him.

Greg handed him a wrapped package. “There, that one’s yours,” he allowed. “Can you guess what it is?”

“A toy fire engine,” said Sherlock immediately. This was met with chiding noises from the others. “Am I wrong?” he challenged.

“Stop spoiling surprises,” John chastised.

“I could’ve figured it out!” Finn protested. Nonetheless he opened the package with glee and found that it was, indeed, a toy fire engine. “Thank you, Uncle Greg,” he said, without prompting, though he was also waiting a bit impatiently for Greg to liberate the toy from its box.

The teakettle whistled. “Sherlock,” John poked. “That’s your cue.” Sherlock got up readily enough, but he was still staring at the tablet. “Sherlock. Darling.” That got his attention immediately and he smiled at John, who smiled back and nearly forgot what he’d been about to say. “Oh, could you leave that behind?” John requested, indicating the tablet. “Don’t want you getting distracted and adding cyanide instead of sugar.”

“You made me move the cyanide _out_ of the kitchen,” Sherlock reminded John, but handed over the tablet anyway.

“I’ll take mine _without_ cyanide, please,” Greg called, in case there was any doubt.

The fire engine freed, Finn began to roll it around the floor, knocking his blocks aside and making a loud whooping noise meant to be a siren. “Have you Arthur’s present?” he inquired, too innocently. “Perhaps I should open it for him.”

“You may guess what it is,” John allowed. “But leave it for Arthur to open himself.”

Greg produced another package. “Give that a guess, then.” Several people turned to Sherlock, as if warning him to be quiet this time.

“I didn’t say anything,” he pointed out, carrying the tea tray in.

Finn turned the package all around, pressed it delicately with his fingers, listened to the sounds it made when shaken, even sniffed it. The look of intense concentration on his face was familiar to both John and Greg, who shared an amused glance as John brought over his tea. “Well, I don’t know what it’s called,” Finn conceded, which was not much concession, “but it’s a large sort of thing, which is yellow, and has a big arm on the front to scoop things.” He demonstrated with his own arm, scooping up some blocks accompanied by robotic grinding noises.

Greg was duly impressed by his deduction. “Very good!” he praised. “It’s an _excavator_.”

“They don’t really make that sort of sound, do they?” Sherlock checked. “That doesn’t seem right.”

“Why don’t you put Arthur’s present out where he can see it,” John told Finn, “and maybe he will come out to look at it.”

Finn set the package in front of the table under which Arthur was hiding. “I told him you were very nice and he oughtn’t be afraid of you,” Finn assured Greg.

“Well, thank you,” Greg replied.

“Unless of course he was a bad guy, then he ought to be _very_ afraid of you,” Finn went on blithely, “because you catch bad guys like Daddy and Jo—Papa do.” He was discouraged by his mistake in titles, but John smiled at him. “How can there be any bad guys left, if you’re catching them all the time?”

Sherlock snorted and started to answer, but he was silenced by a look from John. “That’s right, I’m sure Arthur’s a very good boy, so he’ll get no trouble from me,” Greg agreed, stacking some blocks.

“Yes, Arthur’s very good,” Finn confirmed generously. “He’s very quiet, and that’s quite close to good.”

John choked on his tea. “Now wherever did you get that idea, Finn?” he asked. He could not help glancing at Sherlock, who merely shrugged innocently. “Of course you don’t _always_ need to be quiet—“

“Though a lower volume is preferred,” Sherlock added.

“—we like talking to you very much,” John attempted to continue.

“Only not when we’re having grown-up time,” Sherlock clarified.

“But you must speak up if something’s wrong,” John finished.

This, Sherlock could agree with whole-heartedly. “Yes, be _very_ loud in that case,” he advised.

Finn was used to the table-tennis routine by now and didn’t let it faze him. He was more interested in his fire engine, anyway. “Did you know John is Papa now?” he informed Greg. This was obviously a big thing in his world.

“Is he? That’s nice.”

“It was my idea, but it’s for Arthur,” Finn continued nobly. “Because he rather looks like John, don’t you think?”

“Er, I haven’t seen him yet,” Greg demurred, though he had been informed of the boys’ mysterious laboratory origins finally.

“Well, he does,” Finn asserted, plowing into some blocks. “So he ought not to call John, John, but rather Daddy, only that would be confusing because we already have a Daddy.”

“And goodness knows he gets enough confusion around here already,” John remarked dryly, nudging Sherlock to pay attention to their guest.

“How much hospitality does he require?” Sherlock asked irritably, not looking up from his tablet. “I’m watching a very important video demonstrating a new compound for dissolving flesh and bone—“

“Really?” Greg asked with professional interest.

“Really?” Finn asked with lurid interest.

“ _Really_?” John asked with disgust. “Not now, alright? Look, Arthur’s present is gone,” he redirected Finn. “You’ve missed him.”

“Oh.” Finn was disappointed at least. They could hear the crackling of paper from under the table, then a rattle as Arthur shook the package vigorously.

“Do you want me to get it out for you, Arthur?” John offered. “Bring it here and I will.”

It took some patience, but after a moment the excavator in its box appeared from under the table, clutched by a small hand. Then slowly Arthur raised the tablecloth and peered out, revealing sandy hair and crystal blue eyes of startling familiarity. After a moment he smiled bravely at Greg.

“There he is,” Greg commented, trying to keep it low-key. “Hello, Arthur.”

“Arthur doesn’t speak,” Finn informed him, which Greg was already aware of. “But lots of times I know what he’s thinking anyway.”

“You’re terribly clever,” Greg praised.

“Yes,” Finn agreed.

“Finn,” John chided. He was going to teach _this_ little Holmes to be modest if it killed him. Meanwhile Arthur had made a run for it with his new toy and scrambled up on the couch next to John. “Shall I open this for you, Arthur?” John asked.

“You said you would,” Sherlock pointed out. “That’s why he brought it to you.”

“Yes, I’m trying to _engage_ him,” John replied mildly. “We have talked about this.” Sherlock was irritated by the amount of repetitive conversation in the house now, though John noted _he_ was often the one in need of it. Futilely he tugged at the plastic fasteners imprisoning the toy. “Never mind, I can’t get it,” he admitted to Arthur, after making a show of it. “Take it to Daddy, I’m sure he’s got some tool to use. And turn off that video!” John added to Sherlock, suddenly realizing what Arthur might see.

Fortunately Sherlock was not _entirely_ insensitive to his young charges and flipped the cover over the tablet. “It wouldn’t make any sense, he’d have to see it from the beginning,” he conceded.

“Yes, maybe when he’s older,” John allowed. “In fifteen years or so.”

Arthur handed Sherlock the toy trapped within its box and Sherlock examined it with great seriousness. “Look closely at these bindings, Arthur,” Sherlock suggested, and the boy did so. “Fiendishly clever. If you ever have need to immobilize someone, remember this configuration.”

John looked at him, ready to say his name in yet another exasperated tone, only to find Sherlock was already gazing at him, the tiniest of smirks on his face. John answered it, having another of those moments when he mentally pinched himself because he couldn’t believe he’d snagged a life with _that_ exasperating genius.

Arthur prodded insistently at Sherlock. “Alright, let’s go see what we’ve got in the toolbox,” Sherlock decided, standing. He held out his hand and Arthur grasped it readily, following Sherlock from the room.

“Arthur will be alright,” Finn assured Greg, who was staring after the smaller boy. “I’m going to look out for him.”

“I bet you will, little man,” Greg agreed fondly, ruffling his hair.

**Notes for the Chapter:**

> That's all I have written for Finn! Thanks for reading!


End file.
